/Engine/Plugins/Online/OnlineSubsystem/Source/Public/Interfaces/OnlineIdentityInterface.h
Converts from an online unique id to a PlatformUserId used by application code
The corresponding id or PLATFORMID_NONE if not found
[FPlatformUserId](API\Runtime\Core\Misc\FPlatformUserId) GetPlatformUserIdFromUniqueNetId ( const [FUniqueNetId](API\Runtime\CoreOnline\Online\FUniqueNetId) & UniqueNetId ) const